This invention relates to battery testers that can be incorporated on battery packaging.
Known types of battery testers that are placed on batteries are so called "thermochromic" types. In a thermochromic battery tester there can be two electrodes that are connected by a consumer manually depressing a switch. Once the switch is depressed, the consumer has connected an anode of the battery to a cathode of the battery through the thermochromic tester. The thermochromic tester includes a silver conductor that has a variable width so that the resistance of the conductor also varies along its length. As current travels through the silver conductor, the current generates heat that changes the color of a thermochromic ink display that is over the silver conductor. The thermochromic ink display is arranged as a gauge to indicate the relative capacity of the battery. The higher the current the more heat is generated and the more the gauge will change to indicate that the battery is good.
Sometimes the switch can be hard for people to depress and it can become difficult to tell whether the tester worked or not or whether the battery is good or bad. This can be confusing to a consumer. Depressing the switch makes a direct relatively high conductance connection between the anode and cathode of the cell which can draw significant power and reduce battery lifetime. Battery heat can also give a false indication of the state of charge of the battery.